"Ain't I glad I got out of the Wilderness" seems to date to 1858, in the song Down in Alabam posted in thread 11138 and song sheets Ain't I Glad to Get Out of the Wilderness, of the Civil War period. A Hampton song indicates that it is earlier.

I have found one Black religious song with that line, although several have only 'go in the wilderness'.

Leanin' on de Lord, sung at Hampton. One student there said "My father sang this hymn, and said he knew a time when a great many slaves were allowed to have a revival for two days, while their masters and families had one......" The version the student had:

Go in de wilderness, Leanin' on de Lord.

Oh, brother how d'ye feel, when ye come out de wilderness, come out de wilderness, come out de wilderness. When ye come out de wilderness, Leanin' on de Lord.

1st tenor: I've got a sister in de wilderness All: De wilderness, de wilderness. 2nd tenor: I've got a brother in de wilderness, All: Working for de Lord. Baritone: I've got a cousin in de wilderness, de wilderness, de wilderness Basso: I've got an uncle on the Bowery, working against de Lord. Chorus Hard shell Baptist git out de wilderness (repeat 2x) Hard shell Baptist git out de wilderness, Wait for de Lord.